Minister King declares West Peron greenhouse gas storage formation off northern Australia

Madeleine King, the federal Minister for Resources and Minister for Northern Australia, has declared 34 graticular blocks on the Darwin SD52 map sheet to be an identified greenhouse gas storage formation, to be known as West Peron. The declaration was made under section 312(14) of the Offshore Petroleum and Greenhouse Gas Storage Act 2006 and is dated 12 October 2026. It was registered in the Commonwealth of Australia Gazette on 22 October 2026 as C2026G00685.

The instrument and its legal basis

The notice is signed by King in her capacity as the responsible Commonwealth Minister and states that she “hereby declare[s] the following blocks to be an identified greenhouse gas storage formation”. The document defines “the Act” as the Offshore Petroleum and Greenhouse Gas Storage Act 2006, including any Act with which it is incorporated, and adopts the same meanings for words used in the Act.

The blocks are identified by reference to the name of the map sheet of the 1:1,000,000 series prepared and established for the purposes of the Act, and to the numbers of the graticular sections shown on it. The storage formation is named West Peron and the map sheet is Darwin SD52.

Thirty-four blocks and their spatial extent

The declaration lists the blocks individually, running from block 0608 through to block 1045, and records that the area is “assessed to contain 34 blocks”, with a map at Attachment 1. The estimated lateral spatial extent is within the graticular blocks listed in the table.

The vertical spatial extent is defined as lying between the base of the Plover Formation and the top of the Wangarlu Formation of the Bathurst Island Group.

Fundamental suitability determinants

The notice sets out the fundamental suitability determinants of the West Peron Storage Formation against the relevant paragraphs of section 21(8) of the Act:

• Amount of greenhouse gas substance suitable to store: up to 443 Mt, via a proposed multi-phase project.
• Greenhouse gas substance suitable to store: a minimum of 95% CO2.
• Injection point or points: up to 12 injection wells, located either north of a line extending 13 km southeast from West Peron-2, or within 6.5 km of the meridian passing through West Peron-1.
• Injection period: up to 35 years.
• Engineering enhancements under subsection 21(1)(b): not applicable.
• Effective sealing feature, attribute or mechanism: a migration assisted storage mechanism within a saline aquifer, trapped beneath the regionally extensive mudstones of the Wangarlu Formation of the Bathurst Island Group.

What the declaration means

The instrument is made under the Offshore Petroleum and Greenhouse Gas Storage Act 2006 of the Commonwealth of Australia and is signed by King as Minister for Resources and Minister for Northern Australia. It carries a formal date of 12 October 2026 and was registered in the gazette ten days later.

The declaration converts a defined offshore acreage into a formally identified storage formation, fixing in a public instrument the volume of greenhouse gas the formation is assessed to hold, the purity of the stream it may receive, the number and location of injection wells and the maximum injection period. Those parameters are the technical baseline against which any future injection and storage project in the West Peron area would be assessed.

Source: Commonwealth of Australia Gazette, Government Notices C2026G00685, 22 October 2026 (official reference: C2026G00685).